Any certificate may be revoked for cause at any time. Violation of any provision of the Fair Labor Standards Act shall be sufficient grounds for revocation of all certificates issued to an employer, in which event no certificates shall be issued to the offending employer for a period of up to one year. Before any certificate is cancelled, however, interested parties shall be notified in writing of the facts warranting such cancellation and afforded an opportunity to demonstrate or achieve compliance. In appropriate circumstances, the Administrator shall afford an opportunity for a hearing to resolve the disputed matter.